US6824261B2 - Hollow fiber membrane for the degassing of inks, ink degassing method, ink degassing apparatus, method for the fabrication of an ink cartridge, and ink - Google Patents

Hollow fiber membrane for the degassing of inks, ink degassing method, ink degassing apparatus, method for the fabrication of an ink cartridge, and ink Download PDF

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US6824261B2
US6824261B2 US10/176,575 US17657502A US6824261B2 US 6824261 B2 US6824261 B2 US 6824261B2 US 17657502 A US17657502 A US 17657502A US 6824261 B2 US6824261 B2 US 6824261B2
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ink
hollow fiber
fiber membrane
degassing
inks
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US20020153318A1 (en
Inventor
Kenji Watari
Satoshi Takeda
Masumi Kobayashi
Makoto Uchida
Masamoto Uenishi
Noriaki Fukushima
Seiji Hayashi
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Mitsubishi Chemical Corp
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Mitsubishi Rayon Co Ltd
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Priority claimed from JP2903298A external-priority patent/JPH11209670A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D19/00—Degasification of liquids
    • B01D19/0031—Degasification of liquids by filtration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D63/00—Apparatus in general for separation processes using semi-permeable membranes
    • B01D63/02—Hollow fibre modules
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D63/00—Apparatus in general for separation processes using semi-permeable membranes
    • B01D63/02—Hollow fibre modules
    • B01D63/04—Hollow fibre modules comprising multiple hollow fibre assemblies
    • B01D63/043—Hollow fibre modules comprising multiple hollow fibre assemblies with separate tube sheets
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/02—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor characterised by their properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/08—Hollow fibre membranes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01—Ink jet
    • B41J2/17—Ink jet characterised by ink handling
    • B41J2/19—Ink jet characterised by ink handling for removing air bubbles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2313/00—Details relating to membrane modules or apparatus
    • B01D2313/13—Specific connectors

Definitions

  • This invention relates to a hollow fiber membrane for the degassing of inks which can be used to remove dissolved gases from inks for use in ink-jet printers and the like, an ink degassing method, and an ink degassing apparatus, as well as a method for the fabrication of an ink cartridge by using the same.
  • an ink is delivered from an ink cartridge to a printer head by capillary action.
  • minute air bubbles present in the ink or within the ink cartridge gives flow resistance to the ink.
  • dissolved gases e.g., dissolved oxygen and dissolved nitrogen
  • Methods for removing dissolved gases from an ink are roughly classified into physical methods for degassing an ink by physical means such as boiling or evacuation, and chemical methods for degassing an ink by introducing gas absorbents thereinto.
  • physical methods are disadvantageous, for example, in that the degree of degassing is insufficient or the ink may be deteriorated.
  • chemical methods are also disadvantageous, for example, in that the dye contained in the ink may undergo a chemical change.
  • Japanese Patent Laid-Open No. 17712/'93 discloses a method for the degassing of an ink for use in ink-jet recording which comprises passing the ink through hollow fibers comprising a gas-permeable hollow fiber membrane, and evacuating the outer surface side of the hollow fibers to remove dissolved gases from the ink by permeation through the hollow fiber membrane.
  • the use of a hollow fiber membrane makes it possible to remove dissolved gases efficiently from an ink without exerting an adverse influence on the properties of the ink.
  • hollow fibers having an inner diameter of 20 to 30 ⁇ m are used in the ink degassing method disclosed in Japanese Patent Laid-Open No. 17712/'93. This causes a considerable pressure loss in the hollow fibers and hence requires high mechanical strength for the whole system, resulting in an increased cost.
  • the hollow fibers have a membrane thickness of 10 ⁇ m or less. This is disadvantageous in that, when the outer surface side of the hollow fibers is evacuated by starting a vacuum pump or returned to atmospheric pressure, the hollow fibers tend to vibrate and suffer damage as a result of mutual contact.
  • inks for use in ink-jet printers usually contain a hydrophilic compound such as alcohol or ethylene glycol. Consequently, a method using a porous hollow fiber membrane can maintain high permeability to gases even if the membrane thickness is large.
  • the surface of the porous base material is gradually made hydrophilic by the hydrophilic compound, so that the ink may undesirably leak out through the pores of the membrane.
  • the oxygen and nitrogen permeation fluxes of the teflon membrane are as low as 7.5 to 22.5 ⁇ 10 ⁇ 10 cm 3 /(cm 2 ⁇ Pa ⁇ sec). Consequently, when the hollow fiber membrane has a membrane thickness ensuring adequate mechanical strength, it is difficult to obtain a sufficient gas permeability. As a result, the dissolved gas concentration in the degassed ink has been limited to as high as 6.4 ppm or so.
  • the present invention has been made in view of the above-described disadvantages, and an object thereof is to provide a hollow fiber membrane for the degassing of inks which, when used to remove dissolved gases from an ink, permits the ink to be efficiently degassed with a slight pressure loss in the ink flow path and without any damage to the hollow fiber membrane upon exposure to pressure changes, an ink degassing method, and an ink degassing apparatus.
  • Another object of the present invention is to provide a method for the fabrication of an ink cartridge for use in ink-jet printers wherein the dissolved gas concentrations in the ink are very low.
  • the present invention provides a hollow fiber membrane for the degassing of inks which comprises a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 ⁇ m and a membrane thickness of 10 to 150 ⁇ m.
  • This hollow fiber membrane for the degassing of inks preferably has a three-layer structure consisting of a nonporous layer having porous layers disposed on both sides thereof. In this case, it is preferable that the thickness of the nonporous layer be from 0.3 to 2 ⁇ m and the thickness of the porous layers be from 5 to 100 ⁇ m.
  • the present invention also provides an ink degassing method which comprises the steps of passing an ink through the bores of hollow fibers comprising a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 ⁇ m and a membrane thickness of 10 to 150 ⁇ m, and evacuating the outer surface side of the hollow fibers, whereby dissolved gases are removed from the ink.
  • the present invention also provides an ink degassing apparatus comprising a canister having an ink inlet, an inlet side socket communicating with the ink inlet, an ink outlet, an outlet side socket communicating with the ink outlet, and a gas vent; and a hollow fiber membrane element in which follow fibers comprising a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 ⁇ m and a membrane thickness of 10 to 150 ⁇ m are fastened together with fastening members so that both ends thereof are left open, the two fastening members being connected to the inlet side socket and the outlet side socket, respectively.
  • this apparatus is constructed in such a way that a plurality of hollow fiber membrane elements connected in series are installed within the canister, and an ink confluence chamber is formed in each of the joints therebetween.
  • the present invention also provides a method for the fabrication of an ink cartridge for use in ink-jet printers wherein, when an ink cartridge for use in ink-jet printers is filled with an ink, the ink filling flow path for conducting the ink to the ink cartridge is equipped with follow fibers comprising a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 ⁇ m and a membrane thickness of 10 to 150 ⁇ m, and the outer surface side of the hollow fibers is evacuated to remove dissolved gases from the ink, whereby the total dissolved gas concentration in the ink contained in the ink cartridge is reduced to 2,950 ⁇ g/L or less.
  • follow fibers comprising a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 ⁇ m and a membrane thickness of 10 to 150 ⁇ m
  • the present invention also provides an ink for use in ink-jet printers which has a total dissolved gas concentration of not greater than 2,950 mg/L.
  • FIG. 1 is a schematic sectional view illustrating one embodiment of the ink degassing apparatus of the present invention
  • FIG. 2 is a schematic sectional view illustrating an exemplary hollow fiber membrane element for use in the ink degassing apparatus of the present invention
  • FIG. 3 is a schematic sectional view illustrating another embodiment of the ink degassing apparatus of the present invention.
  • FIG. 4 is a schematic sectional view illustrating an exemplary hollow fiber membrane module for use in the ink degassing apparatus of the present invention.
  • the hollow fiber membrane for the degassing of inks in accordance with the present invention is a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 ⁇ m and a membrane thickness of 10 to 150 ⁇ m.
  • the pressure loss during degassing can be minimized by using the hollow fiber membrane having an inner diameter of 50 to 500 ⁇ m. If the inner diameter is greater than 500 ⁇ m, it will be difficult to reduce the concentration of dissolved gases.
  • variation in pressure causes no damage to the hollow fiber membrane, ensuring that the degassing of inks can be satisfactorily carried out.
  • the inks which can be treated with the hollow fiber membrane for the degassing of inks in accordance with the present invention are aqueous inks for use in ink-jet printers and the like.
  • the solvent consists essentially of water, but various water-soluble organic solvents may be added thereto.
  • the gases to be removed are gases which have dissolved from air into inks, and typically include oxygen and nitrogen. Since the principal ingredient of such inks is water, the solubilities of gases in the inks are considered to be close to their solubilities in water.
  • the solubilities of oxygen and nitrogen in water at 25° C. are 8.3 mg/L and 13.7 mg/L, respectively.
  • the hollow fiber membrane for the degassing of inks in accordance with the present invention may be a porous membrane or a nonporous membrane, provided that it has gas permeability.
  • the surface of the porous base material of the hollow fiber membrane is made hydrophilic by the hydrophilic compound(s) contained in the ink, so that it may be possible for the ink to leak out through the pores of the membrane.
  • the degassing of inks tends to require a long time because of its low oxygen and nitrogen permeation fluxes.
  • the hollow fiber membrane a composite hollow fiber membrane having a three-layer structure consisting of a nonporous layer having porous layers disposed on both sides thereof.
  • Use of such a composite hollow fiber membrane makes it possible to prevent the ink from leaking out through the hollow fiber membrane and to degas the ink with high degassing efficiency.
  • a preferred composite hollow fiber membrane is one in which the thickness of the nonporous layer is from 0.3 to 2 ⁇ m and the thickness of the porous layers disposed on both sides thereof is from 5 to 100 ⁇ m.
  • Such a composite hollow fiber membrane not only has high mechanical strength and is hence less liable to damage or the like, but also exhibits good gas permeability.
  • the nonporous layer becomes less wettable with the ink. This makes it possible to minimize the deterioration of nonporous layer by the ink and to increase the amount of gas permeation during degassing.
  • These composite hollow fiber membranes having a three-layer structure may be prepared, for example, by melt-spinning a polymer for forming a homogeneous layer and a polymer for forming porous layers by means of a composite spinning nozzle of the multiple cylinder type, and then drawing the spun hollow fiber under conditions which permit the parts forming the porous layers to be made porous without making the homogeneous layer porous.
  • the polymer materials which can be used to form the nonporous layer of these composite hollow fiber membranes include, in addition to silicone rubber type polymers having high gas permeability, silicone rubber type polymers such as polydimethylsiloxane and silicone-polycarbonate copolymers; polyolefin type polymers such as poly(4-methylpentene-1) and low-density polyethylene; fluorine-containing polymers such as perfluoroalkyl-containing polymers; cellulose type polymers such as ethyl cellulose; polyphenylene oxide; poly(4-vinylpyridine); and urethane polymers. These polymers may be used alone or in the form of a copolymer or a polymer blend.
  • the polymer materials which can be used to form the porous layers include polyolefin polymers such as polyethylene, polypropylene, poly(3-methylbutene-1) and poly(4-methylpentene-1); fluorine-containing polymers such as polyvinylidene fluoride and polytetrafluoroethylene; polystyrene; polyether-ether-ketones; polyether-ketones; and the like.
  • urethane polymers are preferred because of their high gas permeability and high stability in film formation.
  • polyethylene is preferred because it can yield a highly flexible hollow fiber membrane and it has high stability in film formation.
  • Polypropylene has high durability to chemical solutions, relatively high mechanical strength, and better thermal properties than polyethylene and urethanes, so that it is a more preferred material for both the nonporous layer and the porous layers.
  • Polyolefin type polymers are excellent in that, when used for the nonporous layer, they are scarcely deteriorated by chemical solutions.
  • they when used for the porous layers, they have high durability to chemical solutions and high mechanical strength, so that they exhibit excellent workability in the fabrication of hollow fiber membrane elements.
  • FIG. 1 is a schematic sectional view illustrating an example of the ink degassing apparatus of the present invention.
  • a hollow fiber membrane element is installed within a canister consisting of a canister body 6 and canister caps 7 disposed at the top and bottom thereof.
  • Canister caps 7 are hermetically sealed to canister body 6 by means of gaskets 8 .
  • FIG. 2 is a schematic sectional view illustrating the construction of the hollow fiber membrane element.
  • a large number of hollow fibers 2 comprising a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 ⁇ m and a membrane thickness of 10 to 150 ⁇ m are arranged within a perforated cylindrical case 1 having a multitude of openings or interstices in the wall thereof.
  • these hollow fibers 2 are bundled and fastened together with fastening members 3 so that the ends of the hollow fibers are left open.
  • O-rings 4 for connecting purposes are mounted on the outer periphery of perforated cylindrical case 1 at two positions near both ends thereof.
  • the material of perforated cylindrical case 1 should be one which has adequate mechanical strength and good durability to inks.
  • the materials which can be used for this purpose include, for example, rigid polyvinyl chloride resin, polycarbonates, polysulfone resins, polyolefin resins (e.g., polypropylene), acrylic resins, ABS resin and modified PPO resins.
  • hollow fibers 2 the above-described hollow fiber membrane for the degassing of inks is used.
  • Fastening members 3 function as members for fastening the large number of hollow fibers with both ends thereof left open and for parting the ink flow path airtightly from the evacuated gas flow path.
  • fastening members 3 there may be used members formed by curing a liquid resin selected from epoxy resins, unsaturated polyester resins and polyurethane resins, and members formed by melting a polyolefin or the like and solidifying it by cooling.
  • the hollow fiber membrane element No particular limitation is placed on the form of the hollow fiber membrane element, provided that it has a construction in which both ends of hollow fibers are bundled and fastened together with fastening members and, moreover, drain can be easily removed.
  • a hollow fiber membrane element assembled within a perforated cylindrical case is preferred because this prevents the hollow fibers from being damaged during fabrication of the hollow fiber membrane element and this permits the hollow fiber membrane element to be fabricated with high dimensional accuracy.
  • One of the fastening members of the hollow fiber membrane element is connected to an outlet side socket 10 ′ installed in the upper canister cap 7 so as to communicate with an ink outlet 11 .
  • the other fastening member is connected to an inlet side socket 10 installed in the lower canister cap 7 so as to communicate with an ink inlet 11 .
  • Canister caps 7 connected to the upper and lower ends of canister body 6 are provided with exhaust vents 12 which are connected to a vacuum pump or the like in order to evacuate the canister. By evacuating the canister, dissolved gases are removed from the ink through the hollow fiber membrane. It is to be understood that these exhaust vents may be provided on canister body 6 .
  • An ink is fed through an ink inlet 9 , introduced into the hollow fiber membrane element by way of inlet side socket 10 , and subjected to a degassing treatment through the membrane of the hollow fibers while flowing through the bores of the hollow fibers.
  • the degassed ink is discharged from ink outlet 11 .
  • the degree of vacuum employed for the degassing treatment is preferably not greater than 10 KPa.
  • the degassing treatment is preferably carried out to such an extent that the total dissolved gas concentration in the ink is reduced to 2,950 ppb or less, through it may vary according to the flow rate of the ink being treated, and the oxygen and nitrogen permeabilities of the hollow fiber membrane.
  • total dissolved gas concentration means the sum of the dissolved oxygen concentration and the dissolved nitrogen concentration.
  • Lower canister cap 7 is provided with a drain pipe 13 having a cock 14 and serving to remove any condensate from the canister as required.
  • a drain pipe 13 having a cock 14 and serving to remove any condensate from the canister as required.
  • FIG. 3 is a schematic sectional view illustrating another embodiment of the ink degassing apparatus of the present invention.
  • a hollow fiber membrane module formed by connecting a plurality of hollow fiber membrane elements in series.
  • One of the free fastening members of the hollow fiber membrane module is connected to an inlet side socket 10 communicating with an ink inlet 9
  • the other free fastening member is connected to an outlet side socket 10 ′ communicating with an ink outlet 11 .
  • FIG. 4 is a schematic sectional view illustrating a joint between adjacent hollow fiber membrane elements. Hollow fiber membrane elements are connected in series by means of connectors 5 , and a ink confluence chamber 15 is formed in each joint.
  • Connectors 5 may be may be made of a material which has adequate mechanical strength and good durability to inks.
  • the materials suitable for this purpose include, for example, rigid polyvinyl chloride resin, polycarbonates, polysulfone resins, polyolefin resins (e.g., polypropylene), acrylic resins, ABS resin and modified PPO resins, and metals (e.g., stainless steel).
  • An ink is fed through an ink inlet 9 , introduced into the hollow fiber membrane module installed within the canister, and subjected to a degassing treatment through the membrane of the hollow fibers while flowing through the bores of the hollow fibers.
  • the ink having passed through the hollow fibers of one hollow fiber membrane element is temporarily combined together in an ink confluence chamber 15 formed between adjacent hollow fiber membrane elements, so that the ink is fed to the succeeding hollow fiber membrane element after the dissolved gas concentration in the ink is made uniform. Consequently, as compared with the case in which hollow fiber membrane elements having no ink confluence chamber are used, the degassing efficiency per unit membrane area is improved. This makes it possible to degas an ink at a higher flow rate of the ink being treated.
  • the hollow fiber membrane elements are connected by means of connectors 5 and are hence easy to assemble and dissemble, they can readily be replaced. Moreover, the optimum design can readily be achieved by varying the length of the module or the elements and the number of connectors according to the length of the canister. Furthermore, when a plurality of hollow fiber membrane elements are connected, in addition to the embodiment in which they are connected in series as illustrated in FIG. 3, it is also possible to connect the hollow fiber membrane elements in parallel while using the corresponding number of inlet side sockets and outlet side sockets.
  • the achievable degree of degassing in the ink treated by the method of the present invention may vary according to the flow rate of the ink being treated and the gas permeability of the hollow fiber membrane used, it is preferable to degas the ink until the total dissolved gas concentration in the ink is not greater than 2,950 ⁇ g/L.
  • the frequency of print dot losses in ink-jet recording is reduced to 0.5% or less, resulting in a practically satisfactory high-quality print or image.
  • the term “frequency of print dot losses” means the ratio of the number of unprinted dots to the total number of print dots.
  • a composite hollow fiber membrane having an oxygen permeation flux of not less than 7.5 ⁇ 10 ⁇ 9 cm 3 /(cm 2 ⁇ Pa ⁇ sec) and a nitrogen permeation flux of not less than 0.75 ⁇ 10 ⁇ 9 cm 3 /(cm 2 ⁇ Pa ⁇ sec), provided that the flow rate of the ink being treated is 1 L/min ⁇ m 2 (membrane area).
  • the ink filling flow path for conducting an ink to the ink cartridge is equipped with the above-described ink degassing apparatus, and the outer surface side of the hollow fibers is evacuated to remove dissolved gases from the ink, whereby the total dissolved gas concentration in the ink contained in the ink cartridge is reduced to 2,950 ⁇ g/L or less.
  • ink cartridges for use in ink-jet printers can be fabricated.
  • the ink cartridge When the ink cartridge is filled with the ink having a total dissolved gas concentration of not greater than 2,950 ppb, it is especially preferable to evacuate the ink cartridge and then fill it with the ink. If the ink is fed under pressure without evacuating the ink cartridge, there is a possibility that the pressurizing gas or contaminant gases may be dissolved into the once degassed ink during pressure feeding and, therefore, the present invention may fail to produce its desired effect.
  • the present invention is further illustrated by the following examples.
  • the dissolved oxygen concentration in an ink was measured with an MOCA 3600 Series O 2 Analyzer (manufactured by Orbis Fair Laboratories), and the dissolved nitrogen concentration therein was measured with an MOCA 3610 Series N 2 Analyzer (manufactured by Orbis Fair Laboratories).
  • the thickness of the nonporous layer was 0.8 ⁇ m and the pore diameter of the porous layer was 0.1 ⁇ m.
  • This composite hollow fiber membrane had an oxygen permeation flux of 7.7 ⁇ 10 ⁇ 9 cm 3 /(cm 2 ⁇ Pa ⁇ sec) and a nitrogen permeation flux of 3.0 ⁇ 10 ⁇ 9 cm 3 /(cm 2 ⁇ Pa ⁇ sec).
  • a perforated cylindrical case made of a modified PPO resin a large number of hollow fibers comprising this hollow fiber membrane were bundled and fastened together with fastening members comprising an epoxy resin so that both ends of the hollow fibers were left open.
  • a hollow fiber membrane element as illustrated in FIG. 2 was fabricated.
  • This hollow fiber membrane element had an effective hollow fiber length of 20 cm and a membrane area of 2.4 m 2 .
  • One such hollow fiber membrane element was installed in a canister as illustrated in FIG. 1 . Then, an ink for use in ink-jet printers was degassed by passing it through the hollow fiber membrane element at 25° C. and at a flow rate of 1 L/min and evacuating the outside of the hollow fibers to a pressure of 3 KPa.
  • the dissolved gas concentrations in the ink were 14.1 mg/L for nitrogen and 8.2 mg/L for oxygen.
  • the dissolved nitrogen and oxygen concentrations were reduced to 2,400 ⁇ g/L and 400 ⁇ g/L, respectively.
  • the dissolved gas concentrations in the ink were 13.9 mg/L for nitrogen and 8.3 mg/L for oxygen.
  • the dissolved nitrogen and oxygen concentrations were reduced to 2,330 ⁇ g/L and 280 ⁇ g/L, respectively.
  • Example 1 Three hollow fiber membrane elements similar to that fabricated in Example 1 were connected in series by means of connectors as illustrated in FIG. 4 .
  • the connected hollow fiber membrane elements were installed in a canister as illustrated in FIG. 3, and used to degas an ink under the same conditions as in Example 1.
  • the dissolved gas concentrations in the ink were 14.1 mg/L for nitrogen and 8.2 mg/L for oxygen.
  • the dissolved nitrogen and oxygen concentrations were reduced to 1,800 g/L and 95 ⁇ g/L, respectively.
  • the thickness of the nonporous layer was 0.6 ⁇ m and the pore diameter of the porous layer was 0.1 ⁇ m.
  • This composite hollow fiber membrane had an oxygen permeation flux of 7.6 ⁇ 10 ⁇ 9 cm 3 /(cm 2 ⁇ Pa ⁇ sec) and a nitrogen permeation flux of 2.4 ⁇ 10 ⁇ 9 cm 3 /(cm 2 ⁇ Pa ⁇ sec).
  • three hollow fiber membrane elements having the same construction as that of Example 1 were fabricated. In the same manner as in Example 3, these three hollow fiber membrane elements were connected in series by means of connectors. The connected hollow fiber membrane elements were installed in a canister and used to degas an ink under the same conditions as in Example 1.
  • the dissolved gas concentrations in the ink were 14.0 mg/L for nitrogen and 8.1 mg/L for oxygen.
  • the dissolved nitrogen and oxygen concentrations were reduced to 1,950 ⁇ g/L and 120 ⁇ g/L, respectively.
  • the thickness of the nonporous layer was 0.6 ⁇ m and the pore diameter of the porous layer was 0.03 ⁇ m.
  • This composite hollow fiber membrane had an oxygen permeation flux of 31 ⁇ 10 ⁇ 9 cm 3 /(cm 2 ⁇ Pa ⁇ sec) and a nitrogen permeation flux of 7.8 ⁇ 10 ⁇ 9 cm 3 /(cm 2 ⁇ Pa ⁇ sec).
  • three hollow fiber membrane elements having the same construction as that of Example 1 were fabricated.
  • Example 3 In the same manner as in Example 3, these three hollow fiber membrane elements were connected in series by means of connectors.
  • the connected hollow fiber membrane elements were installed in a canister and used to degas an ink under the same conditions as in Example 1.
  • the dissolved gas concentrations in the ink were 14.0 mg/L for nitrogen and 8.2 mg/L for oxygen.
  • the dissolved nitrogen and oxygen concentrations were reduced to 1,050 ⁇ g/L and 60 ⁇ g/L, respectively.
  • the ink degassing method and ink degassing apparatus of the present invention make it possible not only to degas inks with a slight pressure loss, but also to degas inks stably without any damage to the hollow fiber membrane even if pressure changes occur during degassing.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Water Supply & Treatment (AREA)
  • Degasification And Air Bubble Elimination (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Ink Jet (AREA)

Abstract

The present invention provides a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 μm and a membrane thickness of 10 to 150 μm, which is, preferably a composite hollow fiber membrane having a three-layer structure consisting of a nonporous layer having porous layers disposed on both sides thereof. Dissolved gases present in an ink can be removed by passing the ink through the bores of hollow fibers comprising such a hollow fiber membrane, and evacuating the outer surface side of the hollow fibers. This method makes it possible not only to degas inks with a slight pressure loss, but also to degas inks stably even if pressure changes occur during degassing.

Description

CROSS-REFERENCED APPLICATIONS
This application is a divisional application of U.S. application Ser. No. 09/403,986, physically filed Oct. 29, 1999, but accorded a 35 U.S.C. § 371(c)(1), (2), (4) date of Feb. 1, 2000, now U.S. Pat. No. 6,447,679 B1, which is incorporated herein by reference in its entirety, which was the 371 National phase of International Application No. PCT/JP98/01965, filed April 30, 1998, which was not published in English.
TECHNICAL FIELD
This invention relates to a hollow fiber membrane for the degassing of inks which can be used to remove dissolved gases from inks for use in ink-jet printers and the like, an ink degassing method, and an ink degassing apparatus, as well as a method for the fabrication of an ink cartridge by using the same.
BACKGROUND ART
In ink-jet printers, an ink is delivered from an ink cartridge to a printer head by capillary action. However, it is known that, during delivery of the ink, minute air bubbles present in the ink or within the ink cartridge gives flow resistance to the ink. Moreover, it is also known that, when the ink head is repeatedly pressurized and depressurized during ink ejection, dissolved gases (e.g., dissolved oxygen and dissolved nitrogen) present in the ink tend to stagnate in the ink head and cause print dot losses at the time of ink ejection.
Methods for removing dissolved gases from an ink are roughly classified into physical methods for degassing an ink by physical means such as boiling or evacuation, and chemical methods for degassing an ink by introducing gas absorbents thereinto. However, physical methods are disadvantageous, for example, in that the degree of degassing is insufficient or the ink may be deteriorated. Moreover, chemical methods are also disadvantageous, for example, in that the dye contained in the ink may undergo a chemical change.
In order to solve these problems, Japanese Patent Laid-Open No. 17712/'93 discloses a method for the degassing of an ink for use in ink-jet recording which comprises passing the ink through hollow fibers comprising a gas-permeable hollow fiber membrane, and evacuating the outer surface side of the hollow fibers to remove dissolved gases from the ink by permeation through the hollow fiber membrane. The use of a hollow fiber membrane makes it possible to remove dissolved gases efficiently from an ink without exerting an adverse influence on the properties of the ink.
However, hollow fibers having an inner diameter of 20 to 30 μm are used in the ink degassing method disclosed in Japanese Patent Laid-Open No. 17712/'93. This causes a considerable pressure loss in the hollow fibers and hence requires high mechanical strength for the whole system, resulting in an increased cost. Moreover, the hollow fibers have a membrane thickness of 10 μm or less. This is disadvantageous in that, when the outer surface side of the hollow fibers is evacuated by starting a vacuum pump or returned to atmospheric pressure, the hollow fibers tend to vibrate and suffer damage as a result of mutual contact.
In order to improve their wetting properties and penetrating power into paper, inks for use in ink-jet printers usually contain a hydrophilic compound such as alcohol or ethylene glycol. Consequently, a method using a porous hollow fiber membrane can maintain high permeability to gases even if the membrane thickness is large. However, the surface of the porous base material is gradually made hydrophilic by the hydrophilic compound, so that the ink may undesirably leak out through the pores of the membrane. On the other hand, in a degassing method using a nonporous hollow fiber membrane such as one formed of teflon, the oxygen and nitrogen permeation fluxes of the teflon membrane are as low as 7.5 to 22.5×10−10 cm3/(cm2·Pa·sec). Consequently, when the hollow fiber membrane has a membrane thickness ensuring adequate mechanical strength, it is difficult to obtain a sufficient gas permeability. As a result, the dissolved gas concentration in the degassed ink has been limited to as high as 6.4 ppm or so.
DISCLOSURE OF THE INVENTION
The present invention has been made in view of the above-described disadvantages, and an object thereof is to provide a hollow fiber membrane for the degassing of inks which, when used to remove dissolved gases from an ink, permits the ink to be efficiently degassed with a slight pressure loss in the ink flow path and without any damage to the hollow fiber membrane upon exposure to pressure changes, an ink degassing method, and an ink degassing apparatus.
Another object of the present invention is to provide a method for the fabrication of an ink cartridge for use in ink-jet printers wherein the dissolved gas concentrations in the ink are very low.
That is, the present invention provides a hollow fiber membrane for the degassing of inks which comprises a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 μm and a membrane thickness of 10 to 150 μm. This hollow fiber membrane for the degassing of inks preferably has a three-layer structure consisting of a nonporous layer having porous layers disposed on both sides thereof. In this case, it is preferable that the thickness of the nonporous layer be from 0.3 to 2 μm and the thickness of the porous layers be from 5 to 100 μm.
The present invention also provides an ink degassing method which comprises the steps of passing an ink through the bores of hollow fibers comprising a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 μm and a membrane thickness of 10 to 150 μm, and evacuating the outer surface side of the hollow fibers, whereby dissolved gases are removed from the ink.
Moreover, the present invention also provides an ink degassing apparatus comprising a canister having an ink inlet, an inlet side socket communicating with the ink inlet, an ink outlet, an outlet side socket communicating with the ink outlet, and a gas vent; and a hollow fiber membrane element in which follow fibers comprising a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 μm and a membrane thickness of 10 to 150 μm are fastened together with fastening members so that both ends thereof are left open, the two fastening members being connected to the inlet side socket and the outlet side socket, respectively. Preferably, this apparatus is constructed in such a way that a plurality of hollow fiber membrane elements connected in series are installed within the canister, and an ink confluence chamber is formed in each of the joints therebetween.
Moreover, the present invention also provides a method for the fabrication of an ink cartridge for use in ink-jet printers wherein, when an ink cartridge for use in ink-jet printers is filled with an ink, the ink filling flow path for conducting the ink to the ink cartridge is equipped with follow fibers comprising a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 μm and a membrane thickness of 10 to 150 μm, and the outer surface side of the hollow fibers is evacuated to remove dissolved gases from the ink, whereby the total dissolved gas concentration in the ink contained in the ink cartridge is reduced to 2,950 μg/L or less.
Furthermore, the present invention also provides an ink for use in ink-jet printers which has a total dissolved gas concentration of not greater than 2,950 mg/L.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic sectional view illustrating one embodiment of the ink degassing apparatus of the present invention;
FIG. 2 is a schematic sectional view illustrating an exemplary hollow fiber membrane element for use in the ink degassing apparatus of the present invention;
FIG. 3 is a schematic sectional view illustrating another embodiment of the ink degassing apparatus of the present invention; and
FIG. 4 is a schematic sectional view illustrating an exemplary hollow fiber membrane module for use in the ink degassing apparatus of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
The hollow fiber membrane for the degassing of inks in accordance with the present invention is a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 μm and a membrane thickness of 10 to 150 μm. The pressure loss during degassing can be minimized by using the hollow fiber membrane having an inner diameter of 50 to 500 μm. If the inner diameter is greater than 500 μm, it will be difficult to reduce the concentration of dissolved gases. Moreover, when the hollow fiber membrane having membrane thickness of 10 to 150 μm is used, variation in pressure causes no damage to the hollow fiber membrane, ensuring that the degassing of inks can be satisfactorily carried out.
The inks which can be treated with the hollow fiber membrane for the degassing of inks in accordance with the present invention are aqueous inks for use in ink-jet printers and the like. In these inks, the solvent consists essentially of water, but various water-soluble organic solvents may be added thereto. The gases to be removed are gases which have dissolved from air into inks, and typically include oxygen and nitrogen. Since the principal ingredient of such inks is water, the solubilities of gases in the inks are considered to be close to their solubilities in water. The solubilities of oxygen and nitrogen in water at 25° C. are 8.3 mg/L and 13.7 mg/L, respectively.
The hollow fiber membrane for the degassing of inks in accordance with the present invention may be a porous membrane or a nonporous membrane, provided that it has gas permeability. However, in the case of a porous membrane, the surface of the porous base material of the hollow fiber membrane is made hydrophilic by the hydrophilic compound(s) contained in the ink, so that it may be possible for the ink to leak out through the pores of the membrane. On the other hand, in the case of a nonporous membrane, the degassing of inks tends to require a long time because of its low oxygen and nitrogen permeation fluxes. For these reasons, it is preferable to use, as the hollow fiber membrane, a composite hollow fiber membrane having a three-layer structure consisting of a nonporous layer having porous layers disposed on both sides thereof. Use of such a composite hollow fiber membrane makes it possible to prevent the ink from leaking out through the hollow fiber membrane and to degas the ink with high degassing efficiency.
A preferred composite hollow fiber membrane is one in which the thickness of the nonporous layer is from 0.3 to 2 μm and the thickness of the porous layers disposed on both sides thereof is from 5 to 100 μm. Such a composite hollow fiber membrane not only has high mechanical strength and is hence less liable to damage or the like, but also exhibits good gas permeability. Moreover, when a composite hollow fiber membrane in which the porous layers have a pore size of 0.01 to 1 μm is used, the nonporous layer becomes less wettable with the ink. This makes it possible to minimize the deterioration of nonporous layer by the ink and to increase the amount of gas permeation during degassing.
These composite hollow fiber membranes having a three-layer structure may be prepared, for example, by melt-spinning a polymer for forming a homogeneous layer and a polymer for forming porous layers by means of a composite spinning nozzle of the multiple cylinder type, and then drawing the spun hollow fiber under conditions which permit the parts forming the porous layers to be made porous without making the homogeneous layer porous.
The polymer materials which can be used to form the nonporous layer of these composite hollow fiber membranes include, in addition to silicone rubber type polymers having high gas permeability, silicone rubber type polymers such as polydimethylsiloxane and silicone-polycarbonate copolymers; polyolefin type polymers such as poly(4-methylpentene-1) and low-density polyethylene; fluorine-containing polymers such as perfluoroalkyl-containing polymers; cellulose type polymers such as ethyl cellulose; polyphenylene oxide; poly(4-vinylpyridine); and urethane polymers. These polymers may be used alone or in the form of a copolymer or a polymer blend.
The polymer materials which can be used to form the porous layers include polyolefin polymers such as polyethylene, polypropylene, poly(3-methylbutene-1) and poly(4-methylpentene-1); fluorine-containing polymers such as polyvinylidene fluoride and polytetrafluoroethylene; polystyrene; polyether-ether-ketones; polyether-ketones; and the like.
No particular limitation is placed on the combination of the polymer material forming the nonporous layer and the polymer material forming the porous layers. Not only different types of polymers, but also the same type of polymers may be used.
As the material of the nonporous layer, urethane polymers are preferred because of their high gas permeability and high stability in film formation. As the material of the porous layers, polyethylene is preferred because it can yield a highly flexible hollow fiber membrane and it has high stability in film formation. Polypropylene has high durability to chemical solutions, relatively high mechanical strength, and better thermal properties than polyethylene and urethanes, so that it is a more preferred material for both the nonporous layer and the porous layers. Polyolefin type polymers are excellent in that, when used for the nonporous layer, they are scarcely deteriorated by chemical solutions. Moreover, when used for the porous layers, they have high durability to chemical solutions and high mechanical strength, so that they exhibit excellent workability in the fabrication of hollow fiber membrane elements.
Now, the ink degassing method and ink degassing apparatus of the present invention are described hereinbelow with reference to the accompanying drawings.
FIG. 1 is a schematic sectional view illustrating an example of the ink degassing apparatus of the present invention. A hollow fiber membrane element is installed within a canister consisting of a canister body 6 and canister caps 7 disposed at the top and bottom thereof. Canister caps 7 are hermetically sealed to canister body 6 by means of gaskets 8.
FIG. 2 is a schematic sectional view illustrating the construction of the hollow fiber membrane element. A large number of hollow fibers 2 comprising a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 μm and a membrane thickness of 10 to 150 μm are arranged within a perforated cylindrical case 1 having a multitude of openings or interstices in the wall thereof. At both ends of perforated cylindrical case 1, these hollow fibers 2 are bundled and fastened together with fastening members 3 so that the ends of the hollow fibers are left open. Moreover, O-rings 4 for connecting purposes are mounted on the outer periphery of perforated cylindrical case 1 at two positions near both ends thereof.
The material of perforated cylindrical case 1 should be one which has adequate mechanical strength and good durability to inks. The materials which can be used for this purpose include, for example, rigid polyvinyl chloride resin, polycarbonates, polysulfone resins, polyolefin resins (e.g., polypropylene), acrylic resins, ABS resin and modified PPO resins. For hollow fibers 2, the above-described hollow fiber membrane for the degassing of inks is used.
Fastening members 3 function as members for fastening the large number of hollow fibers with both ends thereof left open and for parting the ink flow path airtightly from the evacuated gas flow path. As fastening members 3, there may be used members formed by curing a liquid resin selected from epoxy resins, unsaturated polyester resins and polyurethane resins, and members formed by melting a polyolefin or the like and solidifying it by cooling.
No particular limitation is placed on the form of the hollow fiber membrane element, provided that it has a construction in which both ends of hollow fibers are bundled and fastened together with fastening members and, moreover, drain can be easily removed. However, a hollow fiber membrane element assembled within a perforated cylindrical case is preferred because this prevents the hollow fibers from being damaged during fabrication of the hollow fiber membrane element and this permits the hollow fiber membrane element to be fabricated with high dimensional accuracy.
One of the fastening members of the hollow fiber membrane element is connected to an outlet side socket 10′ installed in the upper canister cap 7 so as to communicate with an ink outlet 11. The other fastening member is connected to an inlet side socket 10 installed in the lower canister cap 7 so as to communicate with an ink inlet 11.
Canister caps 7 connected to the upper and lower ends of canister body 6 are provided with exhaust vents 12 which are connected to a vacuum pump or the like in order to evacuate the canister. By evacuating the canister, dissolved gases are removed from the ink through the hollow fiber membrane. It is to be understood that these exhaust vents may be provided on canister body 6.
An ink is fed through an ink inlet 9, introduced into the hollow fiber membrane element by way of inlet side socket 10, and subjected to a degassing treatment through the membrane of the hollow fibers while flowing through the bores of the hollow fibers. The degassed ink is discharged from ink outlet 11. The degree of vacuum employed for the degassing treatment is preferably not greater than 10 KPa. The degassing treatment is preferably carried out to such an extent that the total dissolved gas concentration in the ink is reduced to 2,950 ppb or less, through it may vary according to the flow rate of the ink being treated, and the oxygen and nitrogen permeabilities of the hollow fiber membrane. As used herein, the term “total dissolved gas concentration” means the sum of the dissolved oxygen concentration and the dissolved nitrogen concentration.
Lower canister cap 7 is provided with a drain pipe 13 having a cock 14 and serving to remove any condensate from the canister as required. Thus, any drain liquid resulting from the condensation of water vapor and other vapors having evaporated from the ink through the hollow fiber membrane can be easily discharged out of the canister.
FIG. 3 is a schematic sectional view illustrating another embodiment of the ink degassing apparatus of the present invention. In this embodiment, there is used a hollow fiber membrane module formed by connecting a plurality of hollow fiber membrane elements in series. One of the free fastening members of the hollow fiber membrane module is connected to an inlet side socket 10 communicating with an ink inlet 9, and the other free fastening member is connected to an outlet side socket 10′ communicating with an ink outlet 11.
FIG. 4 is a schematic sectional view illustrating a joint between adjacent hollow fiber membrane elements. Hollow fiber membrane elements are connected in series by means of connectors 5, and a ink confluence chamber 15 is formed in each joint. Connectors 5 may be may be made of a material which has adequate mechanical strength and good durability to inks. The materials suitable for this purpose include, for example, rigid polyvinyl chloride resin, polycarbonates, polysulfone resins, polyolefin resins (e.g., polypropylene), acrylic resins, ABS resin and modified PPO resins, and metals (e.g., stainless steel).
An ink is fed through an ink inlet 9, introduced into the hollow fiber membrane module installed within the canister, and subjected to a degassing treatment through the membrane of the hollow fibers while flowing through the bores of the hollow fibers. The ink having passed through the hollow fibers of one hollow fiber membrane element is temporarily combined together in an ink confluence chamber 15 formed between adjacent hollow fiber membrane elements, so that the ink is fed to the succeeding hollow fiber membrane element after the dissolved gas concentration in the ink is made uniform. Consequently, as compared with the case in which hollow fiber membrane elements having no ink confluence chamber are used, the degassing efficiency per unit membrane area is improved. This makes it possible to degas an ink at a higher flow rate of the ink being treated.
Since the hollow fiber membrane elements are connected by means of connectors 5 and are hence easy to assemble and dissemble, they can readily be replaced. Moreover, the optimum design can readily be achieved by varying the length of the module or the elements and the number of connectors according to the length of the canister. Furthermore, when a plurality of hollow fiber membrane elements are connected, in addition to the embodiment in which they are connected in series as illustrated in FIG. 3, it is also possible to connect the hollow fiber membrane elements in parallel while using the corresponding number of inlet side sockets and outlet side sockets.
Although the achievable degree of degassing in the ink treated by the method of the present invention may vary according to the flow rate of the ink being treated and the gas permeability of the hollow fiber membrane used, it is preferable to degas the ink until the total dissolved gas concentration in the ink is not greater than 2,950 μg/L. When the total dissolved gas concentration in the ink is not greater than 2,950 μg/L, the frequency of print dot losses in ink-jet recording is reduced to 0.5% or less, resulting in a practically satisfactory high-quality print or image. As used herein, the term “frequency of print dot losses” means the ratio of the number of unprinted dots to the total number of print dots.
In order to reduce the total dissolved gas concentration in the ink to 2,950 μg/L or less, it is preferable to use a composite hollow fiber membrane having an oxygen permeation flux of not less than 7.5×10−9 cm3/(cm2·Pa·sec) and a nitrogen permeation flux of not less than 0.75×10−9 cm3/(cm2·Pa·sec), provided that the flow rate of the ink being treated is 1 L/min·m2 (membrane area).
When an ink cartridge for use in ink-jet printers is fabricated by utilizing the above-described ink degassing method and ink degassing apparatus of the present invention, the ink filling flow path for conducting an ink to the ink cartridge is equipped with the above-described ink degassing apparatus, and the outer surface side of the hollow fibers is evacuated to remove dissolved gases from the ink, whereby the total dissolved gas concentration in the ink contained in the ink cartridge is reduced to 2,950 μg/L or less. Thus, ink cartridges for use in ink-jet printers can be fabricated.
When the ink cartridge is filled with the ink having a total dissolved gas concentration of not greater than 2,950 ppb, it is especially preferable to evacuate the ink cartridge and then fill it with the ink. If the ink is fed under pressure without evacuating the ink cartridge, there is a possibility that the pressurizing gas or contaminant gases may be dissolved into the once degassed ink during pressure feeding and, therefore, the present invention may fail to produce its desired effect.
The present invention is further illustrated by the following examples. In these examples, the dissolved oxygen concentration in an ink was measured with an MOCA 3600 Series O2 Analyzer (manufactured by Orbis Fair Laboratories), and the dissolved nitrogen concentration therein was measured with an MOCA 3610 Series N2 Analyzer (manufactured by Orbis Fair Laboratories).
EXAMPLE 1
A composite hollow fiber membrane having an inner diameter of 200 μm and a membrane thickness of 40 μm and consisting of a nonporous layer formed of a segmented polyurethane [Tecoflex EG80A (trade name), manufactured by Thermedix Co., Ltd.; MRF=15; density=1.04] and porous layers formed of high-density polyethylene [Hizex 2200J (trade name), manufactured by Mitsui Chemical Co., Ltd.; MRF=5.2; density=0.968] and disposed on both sides of the nonporous layer was provided. The thickness of the nonporous layer was 0.8 μm and the pore diameter of the porous layer was 0.1 μm. This composite hollow fiber membrane had an oxygen permeation flux of 7.7×10−9 cm3/(cm2·Pa·sec) and a nitrogen permeation flux of 3.0×10−9 cm3/(cm2·Pa·sec). In a perforated cylindrical case made of a modified PPO resin, a large number of hollow fibers comprising this hollow fiber membrane were bundled and fastened together with fastening members comprising an epoxy resin so that both ends of the hollow fibers were left open. Thus, a hollow fiber membrane element as illustrated in FIG. 2 was fabricated. This hollow fiber membrane element had an effective hollow fiber length of 20 cm and a membrane area of 2.4 m2.
One such hollow fiber membrane element was installed in a canister as illustrated in FIG. 1. Then, an ink for use in ink-jet printers was degassed by passing it through the hollow fiber membrane element at 25° C. and at a flow rate of 1 L/min and evacuating the outside of the hollow fibers to a pressure of 3 KPa.
Before the degassing treatment, the dissolved gas concentrations in the ink were 14.1 mg/L for nitrogen and 8.2 mg/L for oxygen. As a result of this treatment, the dissolved nitrogen and oxygen concentrations were reduced to 2,400 μg/L and 400 μg/L, respectively.
EXAMPLE 2
A hollow fiber membrane element having the same construction as that of Example 1, except that the effective hollow fiber length was 60 cm, was fabricated. This hollow fiber membrane element was installed in a canister and used to degas an ink under the same conditions as in Example 1.
Before the degassing treatment, the dissolved gas concentrations in the ink were 13.9 mg/L for nitrogen and 8.3 mg/L for oxygen. As a result of this treatment, the dissolved nitrogen and oxygen concentrations were reduced to 2,330 μg/L and 280 μg/L, respectively.
EXAMPLE 3
Three hollow fiber membrane elements similar to that fabricated in Example 1 were connected in series by means of connectors as illustrated in FIG. 4. The connected hollow fiber membrane elements were installed in a canister as illustrated in FIG. 3, and used to degas an ink under the same conditions as in Example 1.
Before the degassing treatment, the dissolved gas concentrations in the ink were 14.1 mg/L for nitrogen and 8.2 mg/L for oxygen. As a result of this treatment, the dissolved nitrogen and oxygen concentrations were reduced to 1,800 g/L and 95 μg/L, respectively.
EXAMPLE 4
A composite hollow fiber membrane having an inner diameter of 180 μm and a membrane thickness of 35 μm and consisting of a nonporous layer formed of a propylene polymer [Toughmer XR106L (trade name), manufactured by Mitsui Chemical Co., Ltd.; MRF=8; density=0.89] and porous layers formed of polypropylene [J-115G, manufactured by Ube Industries Ltd.; MRF=15; density=0.89] and disposed on both sides of the nonporous layer was provided. The thickness of the nonporous layer was 0.6 μm and the pore diameter of the porous layer was 0.1 μm. This composite hollow fiber membrane had an oxygen permeation flux of 7.6×10−9 cm3/(cm2·Pa·sec) and a nitrogen permeation flux of 2.4×10−9 cm3/(cm2·Pa·sec). Using hollow fibers comprising this composite hollow fiber membrane, three hollow fiber membrane elements having the same construction as that of Example 1 were fabricated. In the same manner as in Example 3, these three hollow fiber membrane elements were connected in series by means of connectors. The connected hollow fiber membrane elements were installed in a canister and used to degas an ink under the same conditions as in Example 1.
Before the degassing treatment, the dissolved gas concentrations in the ink were 14.0 mg/L for nitrogen and 8.1 mg/L for oxygen. As a result of the above-described degassing treatment, the dissolved nitrogen and oxygen concentrations were reduced to 1,950 μg/L and 120 μg/L, respectively.
EXAMPLE 5
A composite hollow fiber membrane having an inner diameter of 195 μm and a membrane thickness of 35 μm and consisting of a nonporous layer formed of poly(4-methylpentene-1) [TPX-MX002 (trade name), manufactured by Mitsui Chemical Co., Ltd.; MRF=22; density=0.835] and porous layers formed of poly(4-methylpentene-1) [TPX-RT31 (trade name), manufactured by Mitsui Chemical Co., Ltd.; MRF=26; density=0.833] and disposed on both sides of the nonporous layer was provided. The thickness of the nonporous layer was 0.6 μm and the pore diameter of the porous layer was 0.03 μm. This composite hollow fiber membrane had an oxygen permeation flux of 31×10−9 cm3/(cm2·Pa·sec) and a nitrogen permeation flux of 7.8×10−9 cm3/(cm2·Pa·sec). Using hollow fibers comprising this composite hollow fiber membrane, three hollow fiber membrane elements having the same construction as that of Example 1 were fabricated.
In the same manner as in Example 3, these three hollow fiber membrane elements were connected in series by means of connectors. The connected hollow fiber membrane elements were installed in a canister and used to degas an ink under the same conditions as in Example 1.
Before the degassing treatment, the dissolved gas concentrations in the ink were 14.0 mg/L for nitrogen and 8.2 mg/L for oxygen. As a result of the above-described degassing treatment, the dissolved nitrogen and oxygen concentrations were reduced to 1,050 μg/L and 60 μg/L, respectively.
The ink degassing method and ink degassing apparatus of the present invention make it possible not only to degas inks with a slight pressure loss, but also to degas inks stably without any damage to the hollow fiber membrane even if pressure changes occur during degassing.

Claims (2)

What is claimed is:
1. A method for the fabrication of an ink cartridge for use in ink-jet printers wherein, when an ink cartridge for use in ink-jet printers is filled with an ink, the ink filling flow path for conducting the ink to the ink cartridge is equipped with hollow fibers comprising a gas-permeable hollow fiber membrane having an inner diameter of 50 to 500 μm and a membrane thickness of 10 to 150 μm, and the outer surface side of the hollow fibers is evacuated to remove dissolved gases from the ink, whereby the total dissolved gas concentration in the ink contained in the ink cartridge is reduced to 2,950 μg/L or less.
2. A method as claimed in claim 1 wherein the hollow fiber membrane is a composite hollow fiber membrane having a three-layer structure consisting of a nonporous layer having porous layers disposed on both sides thereof.
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070052782A1 (en) * 2005-09-05 2007-03-08 Samsung Electronics Co., Ltd. Ink circulation device having degassing function
US20080309706A1 (en) * 2007-06-15 2008-12-18 Seiko Epson Corporation Liquid ejecting apparatus
US20090145638A1 (en) * 2007-12-11 2009-06-11 Seiko Epson Corporation Conductive pattern formation ink, conductive pattern and wiring substrate
US20090145640A1 (en) * 2007-12-10 2009-06-11 Seiko Epson Corporation Conductive pattern formation ink, method of forming conductive pattern, conductive pattern and wiring substrate
US20140043414A1 (en) * 2012-08-08 2014-02-13 Hitachi Industrial Equipment Systems Co., Ltd. Gas-liquid separator and inkjet recording apparatus using the same
US20150258803A1 (en) * 2014-03-14 2015-09-17 Seiko Epson Corporation Liquid storage container

Families Citing this family (46)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE69837974T2 (en) * 1997-04-30 2008-02-21 Mitsubishi Rayon Co., Ltd. DEVICE AND METHOD FOR DEHUMIDIFYING INK AND METHOD FOR PRODUCING INK CARTRIDGES
CA2368206C (en) 1999-04-02 2007-06-26 Mitsubishi Rayon Co., Ltd. Hollow fiber membrane module, its potting material and chemical deaeration method
US6558450B2 (en) * 2001-03-22 2003-05-06 Celgard Inc. Method for debubbling an ink
US6585362B2 (en) 2001-10-05 2003-07-01 Eastman Kodak Company Ink composition, ink cartridge having ink composition, and method of filling ink cartridge
US6652088B1 (en) * 2002-05-13 2003-11-25 Creo Srl High throughput inkjet printing system
JP4341947B2 (en) * 2002-06-14 2009-10-14 株式会社潤工社 Separation membrane module
JP4242171B2 (en) * 2003-02-21 2009-03-18 メタウォーター株式会社 Filter and filter module
US6939392B2 (en) 2003-04-04 2005-09-06 United Technologies Corporation System and method for thermal management
US7922902B2 (en) * 2003-10-30 2011-04-12 Mitsubishi Rayon Co., Ltd. Hollow fiber membrane module, hollow fiber membrane module unit, and water treatment method
WO2005112659A2 (en) * 2004-05-21 2005-12-01 Cornell Research Foundation, Inc. Extended shelf life and bulk transport of perishable organic liquids with low pressure carbon dioxide
DE602005020108D1 (en) * 2004-12-28 2010-05-06 Canon Kk Liquid container and liquid supply apparatus
US7393388B2 (en) 2005-05-13 2008-07-01 United Technologies Corporation Spiral wound fuel stabilization unit for fuel de-oxygenation
US7435283B2 (en) 2005-05-18 2008-10-14 United Technologies Corporation Modular fuel stabilization system
US7465336B2 (en) 2005-06-09 2008-12-16 United Technologies Corporation Fuel deoxygenation system with non-planar plate members
US7377112B2 (en) 2005-06-22 2008-05-27 United Technologies Corporation Fuel deoxygenation for improved combustion performance
US7615104B2 (en) 2005-11-03 2009-11-10 United Technologies Corporation Fuel deoxygenation system with multi-layer oxygen permeable membrane
JP5731093B2 (en) * 2005-11-30 2015-06-10 コニカミノルタ株式会社 Inkjet ink degassing method and inkjet ink manufacturing method
US7569099B2 (en) 2006-01-18 2009-08-04 United Technologies Corporation Fuel deoxygenation system with non-metallic fuel plate assembly
US7582137B2 (en) 2006-01-18 2009-09-01 United Technologies Corporation Fuel deoxygenator with non-planar fuel channel and oxygen permeable membrane
US7824470B2 (en) 2006-01-18 2010-11-02 United Technologies Corporation Method for enhancing mass transport in fuel deoxygenation systems
JP2010076413A (en) * 2007-12-11 2010-04-08 Seiko Epson Corp Liquid supply device and liquid jetting apparatus
EP3520837A1 (en) * 2008-01-18 2019-08-07 Fresenius Medical Care Holdings, Inc. A wearable dialysis system
WO2010059395A1 (en) * 2008-10-30 2010-05-27 Porous Media Corporation Venting and filtration systems with gas permeable membrane
US20100310743A1 (en) * 2009-06-04 2010-12-09 Dean Intellectual Property Services, Inc. Removing gas additives from raw milk
US8506685B2 (en) * 2009-08-17 2013-08-13 Celgard Llc High pressure liquid degassing membrane contactors and methods of manufacturing and use
US20110076359A1 (en) * 2009-09-28 2011-03-31 Dean Intellectual Property Services, Inc. Removing gas additives from raw milk
JP5378180B2 (en) * 2009-12-02 2013-12-25 愛三工業株式会社 Separation membrane module and evaporative fuel processing apparatus having the same
US8430949B2 (en) * 2011-03-25 2013-04-30 Idex Health & Science Llc Apparatus for pervaporation control in liquid degassing systems
US8945387B2 (en) * 2011-08-18 2015-02-03 General Electric Company Hollow fiber membrane module for use in a tubular pressure vessel
KR20140134684A (en) * 2012-03-30 2014-11-24 미쯔비시 레이온 가부시끼가이샤 Composite hollow fiber membrane and hollow fiber membrane module
JP6104560B2 (en) * 2012-10-23 2017-03-29 株式会社ミマキエンジニアリング Printing apparatus, ink supply apparatus, and printing method
JP6098264B2 (en) 2013-03-21 2017-03-22 セイコーエプソン株式会社 Recording device
US20150015645A1 (en) * 2013-07-11 2015-01-15 Loc V. Bui Degassing apparatus and methods thereof
CN105517693B (en) * 2013-07-24 2018-03-06 三菱化学株式会社 Outside pouring type hollow fiber film assembly and the ink-jet printer with the component
WO2015138723A1 (en) * 2014-03-13 2015-09-17 Celgard, Llc Asymmetric membranes and related methods
CA2891161A1 (en) * 2014-05-28 2015-11-28 Chemetics Inc. Membrane separation at high temperature differential
US10086314B2 (en) 2015-03-19 2018-10-02 Helgesen Industries, Inc. Fluid storage reservoir with flow dynamic fluid management and hydronucleation
JP6462131B2 (en) * 2016-05-11 2019-01-30 三菱ケミカル・クリンスイ株式会社 Hollow fiber membrane module
JP6854822B2 (en) * 2016-08-17 2021-04-07 三菱ケミカル・クリンスイ株式会社 Hollow fiber membrane module, degassing air supply device, inkjet printer and carbonated spring manufacturing device
DE102017114166A1 (en) * 2017-06-27 2018-12-27 Océ Holding B.V. Device and method for degassing a printer liquid
US11338588B2 (en) 2018-12-20 2022-05-24 Kateeva, Inc. Print material feed system
CN113226525A (en) * 2018-12-27 2021-08-06 3M创新有限公司 Asymmetric hollow fiber membranes and methods of making and using the same
CN113226526B (en) 2018-12-27 2024-05-14 舒万诺知识产权公司 Hollow fiber membranes with nucleating agents and methods of making and using the same
US11331629B2 (en) * 2019-06-03 2022-05-17 Hamilton Sundstrand Corporation Modular liquid degassing systems
CN114618321B (en) * 2020-12-11 2023-07-25 中国科学院大连化学物理研究所 Hollow fiber membrane, preparation and application thereof in hydraulic oil degassing
WO2022140604A1 (en) * 2020-12-23 2022-06-30 Repligen Corporation Venting or degassing of filter devices and filtration systems

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4489334A (en) * 1981-06-17 1984-12-18 Epson Corporation Immersible oxygen absorbing capsule for ink jet fluid supply
EP0206354A2 (en) 1985-06-27 1986-12-30 Mitsubishi Rayon Co., Ltd. Multilayer composite hollow fibers and method of making same
JPS63264127A (en) 1987-04-22 1988-11-01 Dainippon Ink & Chem Inc Porous membrane type gas-liquid contact device
US5092926A (en) * 1988-10-03 1992-03-03 Seiko Epson Corporation Ink-jet printing ink
JPH0517712A (en) 1991-07-08 1993-01-26 Seiko Epson Corp Deaeration of ink for ink-jet recording
JPH05184812A (en) 1992-01-08 1993-07-27 Mitsubishi Rayon Co Ltd Hollow-fiber membrane module for deaeration
US5254143A (en) * 1990-07-09 1993-10-19 Dainippon Ink And Chemical, Inc. Diaphragm for gas-liquid contact, gas-liquid contact apparatus and process for producing liquid containing gas dissolved therein
JPH06335623A (en) 1993-05-28 1994-12-06 Dainippon Ink & Chem Inc Deaerating film and deaerating method
JPH07171555A (en) 1993-12-21 1995-07-11 Mitsubishi Rayon Co Ltd Deaerated water separation device
US5820659A (en) * 1994-05-19 1998-10-13 L'air Liquide, Societe Anonyme Pour L'etude Et, L'exploitation Des Procedes Georges Claude Multicomponent or asymmetric gas separation membranes
US6270211B1 (en) * 1999-07-07 2001-08-07 Lexmark International, Inc. Bubble elimination and filter tower structure
US6379796B1 (en) * 1997-10-02 2002-04-30 Mitsubishi Rayon Co., Ltd. Composite hollow fiber membrane
US6447679B1 (en) * 1997-04-30 2002-09-10 Mitsubishi Rayon Company, Limited Hollow fiber membrane

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ATE144725T1 (en) * 1992-05-18 1996-11-15 Minntech Corp HOLLOW FIBER FILTER CARTRIDGE AND METHOD FOR THE PRODUCTION THEREOF

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4489334A (en) * 1981-06-17 1984-12-18 Epson Corporation Immersible oxygen absorbing capsule for ink jet fluid supply
EP0206354A2 (en) 1985-06-27 1986-12-30 Mitsubishi Rayon Co., Ltd. Multilayer composite hollow fibers and method of making same
JPS621404A (en) 1985-06-27 1987-01-07 Mitsubishi Rayon Co Ltd Poly-composite hollow fiber membrane and its manufacturing process
US4713292A (en) * 1985-06-27 1987-12-15 Mitsubishi Rayon Co., Ltd. Multilayer composite hollow fibers and method of making same
US4802942A (en) * 1985-06-27 1989-02-07 Mitsubishi Rayon Co., Ltd. Method of making multilayer composite hollow fibers
JPS63264127A (en) 1987-04-22 1988-11-01 Dainippon Ink & Chem Inc Porous membrane type gas-liquid contact device
US5092926A (en) * 1988-10-03 1992-03-03 Seiko Epson Corporation Ink-jet printing ink
US5254143A (en) * 1990-07-09 1993-10-19 Dainippon Ink And Chemical, Inc. Diaphragm for gas-liquid contact, gas-liquid contact apparatus and process for producing liquid containing gas dissolved therein
JPH0517712A (en) 1991-07-08 1993-01-26 Seiko Epson Corp Deaeration of ink for ink-jet recording
JPH05184812A (en) 1992-01-08 1993-07-27 Mitsubishi Rayon Co Ltd Hollow-fiber membrane module for deaeration
JPH06335623A (en) 1993-05-28 1994-12-06 Dainippon Ink & Chem Inc Deaerating film and deaerating method
JPH07171555A (en) 1993-12-21 1995-07-11 Mitsubishi Rayon Co Ltd Deaerated water separation device
US5820659A (en) * 1994-05-19 1998-10-13 L'air Liquide, Societe Anonyme Pour L'etude Et, L'exploitation Des Procedes Georges Claude Multicomponent or asymmetric gas separation membranes
US6447679B1 (en) * 1997-04-30 2002-09-10 Mitsubishi Rayon Company, Limited Hollow fiber membrane
US6379796B1 (en) * 1997-10-02 2002-04-30 Mitsubishi Rayon Co., Ltd. Composite hollow fiber membrane
US6270211B1 (en) * 1999-07-07 2001-08-07 Lexmark International, Inc. Bubble elimination and filter tower structure

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070052782A1 (en) * 2005-09-05 2007-03-08 Samsung Electronics Co., Ltd. Ink circulation device having degassing function
US20080309706A1 (en) * 2007-06-15 2008-12-18 Seiko Epson Corporation Liquid ejecting apparatus
US8287106B2 (en) * 2007-06-15 2012-10-16 Seiko Epson Corporation Liquid ejecting apparatus
US20090145640A1 (en) * 2007-12-10 2009-06-11 Seiko Epson Corporation Conductive pattern formation ink, method of forming conductive pattern, conductive pattern and wiring substrate
US20090145638A1 (en) * 2007-12-11 2009-06-11 Seiko Epson Corporation Conductive pattern formation ink, conductive pattern and wiring substrate
US8173050B2 (en) 2007-12-11 2012-05-08 Seiko Epson Corporation Conductive pattern formation ink, conductive pattern and wiring substrate
US20140043414A1 (en) * 2012-08-08 2014-02-13 Hitachi Industrial Equipment Systems Co., Ltd. Gas-liquid separator and inkjet recording apparatus using the same
US9308738B2 (en) * 2012-08-08 2016-04-12 Hitachi Industrial Equipment Systems Co., Ltd. Gas-liquid separator and inkjet recording apparatus using the same
US9481175B2 (en) 2012-08-08 2016-11-01 Hitachi Industrial Equipment Systems Co., Ltd. Gas-liquid separator and inkjet recording apparatus using the same
US9744769B2 (en) 2012-08-08 2017-08-29 Hitachi Industrial Equipment Systems Co., Ltd. Gas-liquid separator and inkjet recording apparatus using the same
US20150258803A1 (en) * 2014-03-14 2015-09-17 Seiko Epson Corporation Liquid storage container
US9434175B2 (en) * 2014-03-14 2016-09-06 Seiko Epson Corporation Liquid storage container

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US20020158000A1 (en) 2002-10-31
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